The invention relates generally to firearms, and, more particularly, to a retractable shoulder stock for a firearm and a catch lever for such a shoulder stock.
The terms used in this document to describe relative position, such as xe2x80x9cforward,xe2x80x9d xe2x80x9ctop,xe2x80x9d xe2x80x9cleftxe2x80x9d and so forth are referenced to a weapon which is properly positioned to deliver a horizontal shot, with the direction of shooting being toward the front (i.e., away from the shooter). The same convention also applies to the corresponding directional references (xe2x80x9ctoward the front,xe2x80x9d xe2x80x9ctoward the top,xe2x80x9d xe2x80x9cto the left,xe2x80x9d and so forth).
Automatic guns or machine guns often have an extendable shoulder stock which is mounted on guide rods and which can be secured by means of a catch mechanism. In U.S. Pat. No. 3,570,162, for example, the shoulder stock is mounted on a rod which is guided in a pipe so that it can be displaced longitudinally. A retaining claw passes through the pipe wall and engages in a corresponding catch notch of the rod so that the shoulder stock can be secured in the inserted and extracted positions. U.S. Pat. No. 4,383,384 also discloses an extendable shoulder stock. That shoulder stock is guided by two parallel rods, one of which can be locked by a catch pin which engages in corresponding recesses in the rod.
In addition, U.S. Pat. No. 3,137,958 describes an adjustable shoulder stock which is guided by two parallel extractable rods. The rods have catch notches. A catch body that is displaceable across the rods is engaged in the catch notches, thereby securing the position of the shoulder stock. U.S. Pat. No. 5,367,812 discloses another adjusting mechanism, where the rods mounted on the shoulder stock can be extended by means of screw-on elements.
Finally, German Utility Model 88 07 539 U1 discloses a shoulder stock with a receiving pipe in which a supporting rod or a supporting pipe can be telescoped and locked in position. The supporting rod or pipe is locked by locking screws which engage in the supporting rod or supporting pipe when in the desired position.
These known arrangements have the disadvantage that there is a certain play in the shoulder stock even in the locked state. This play has a negative effect on the stability of the gun, which stability is necessary to deliver a well-aimed shot.
A much better solution has been found to be the shoulder stock known from German Patent 1,225,517 by the owner of the present patent. The stock disclosed in that patent is mounted on slide rails which can be locked at the end of the gun casing by a locking element that is mounted so it can rotate. Locking projections of this element engage in corresponding recesses on the slide rail, preferably in such a way that they are put under tension in the radial direction to the axis of rotation of the locking element. Due to this tension, the shoulder stock has an increased stability in the locked state comparable to that of a one-piece rigid gun butt.
In a preferred implementation of the shoulder stock of German Patent 1,225,517, the locking element is designed as a ring-shaped base body and is mounted on a sleeve-shaped casing in the interior of the gun casing. The locking element is, thus, engaged with an operating ring which is used to operate the locking element. The operating ring is provided with an operating wing and is mounted outside the gun casing. This design is characterized by a great robustness and reliability and has proven successful in long-term use (e.g., in the case of the G3 gun of the Deutsche Bundeswehr [German military]). In particular, the shoulder stock is also capable of absorbing high forces, such as that required when firing shells or grenades, for example.
However, the design also includes disadvantages. For example, this design is relatively heavy and takes up a lot of space due to the massive cylinder-shaped construction. It, therefore, seems overdimensioned for certain applications (e.g., for light machine guns or other weapons that do not have such high stability requirements).
In accordance with an aspect of the invention, a retractable shoulder stock is provided for use with a firearm having a casing . The retractable shoulder stock includes a slide rail which is displaceable relative to the casing of the firearm. The slide rail defines at least one recess. The shoulder stock also includes a catch lever which is mounted for rotation about an axis. The catch lever has a peripheral surface that can be manually engaged to rotate the catch lever about the axis. The catch lever is positioned to selectively engage in the at least one recess to releasably lock the slide rail in a first predetermined position.
In accordance with another aspect of the invention, a method of releasably securing a retractable stock of a firearm in a first predetermined position is provided. The method includes the steps of: pivoting a catch lever to disengage the catch lever from a first recess defined in a slide rail associated with the retractable stock; moving the slide rail; and pivoting the catch lever to engage a second recess defined in the slide rail.
Other features and advantages are inherent in the disclosed apparatus or will become apparent to those skilled in the art from the following detailed description and its accompanying drawings.